A Preliminary Study Examining the Binding Capacity of Akkermansia muciniphila and Desulfovibrio spp., to Colonic Mucin in Health and Ulcerative Colitis

BackgroundAkkermansia muciniphila and Desulfovibrio spp. are commensal microbes colonising the mucus gel layer of the colon. Both species have the capacity to utilise colonic mucin as a substrate. A. muciniphila degrades colonic mucin, while Desulfovibrio spp. metabolise the sulfate moiety of sulfated mucins. Altered abundances of these microorganisms have been reported in ulcerative colitis (UC). However their capacity to bind to human colonic mucin, and whether this binding capacity is affected by changes in mucin associated with UC, remain to be defined.MethodsMucin was isolated from resected colon from control patients undergoing resection for colonic cancer (n = 7) and patients undergoing resection for UC (n = 5). Isolated mucin was purified and printed onto mucin microarrays. Binding of reference strains and three clinical isolates of A. muciniphila and Desulfovibrio spp. to purified mucin was investigated.ResultsBoth A. muciniphila and Desulfovibro spp. bound to mucin. The reference strain and all clinical isolates of A. muciniphila showed increased binding capacity for UC mucin (p Desulfovibrio reference strain showed increased affinity for UC mucin. The mucin binding profiles of clinical isolates of Desulfovibrio spp. were specific to each isolate. Two isolates showed no difference in binding. One UC isolate bound with increased affinity to UC mucin (p ConclusionThese preliminary data suggest that differences exist in the mucin binding capacity of isolates of A. muciniphila and Desulfovibrio spp. This study highlights the mucin microarray platform as a means of studying the ability of bacteria to interact with colonic mucin in health and disease.研究背景：阿克曼氏菌（Akkermansia muciniphila）与脱硫弧菌属（Desulfovibrio spp.）是定殖于结肠黏液凝胶层的共生微生物。两类菌种均能够以结肠黏蛋白作为代谢底物：阿克曼氏菌可降解结肠黏蛋白，而脱硫弧菌属则可代谢硫酸化黏蛋白的硫酸基团。已有研究报道，溃疡性结肠炎（ulcerative colitis, UC）患者体内这两类微生物的丰度存在异常。但目前关于二者结合人结肠黏蛋白的能力，以及该结合能力是否会受UC相关黏蛋白变化的影响，仍有待明确。 研究方法：本研究从因结肠癌接受结肠切除术的对照患者（n=7）以及因溃疡性结肠炎接受切除术的患者（n=5）的切除结肠组织中分离黏蛋白。将分离得到的黏蛋白进行纯化后，点印至黏蛋白微阵列（mucin microarray）上。随后探究了参考菌株及3株临床分离的阿克曼氏菌和脱硫弧菌属菌株与纯化黏蛋白的结合情况。 研究结果：阿克曼氏菌与脱硫弧菌属菌株均可结合黏蛋白。所有阿克曼氏菌参考菌株及临床分离株对UC患者来源的黏蛋白均表现出更高的结合能力（p [原文内容缺失]）；脱硫弧菌属参考菌株对UC黏蛋白的亲和力同样升高。脱硫弧菌属临床分离株的黏蛋白结合谱因菌株而异：其中2株分离株的结合能力无显著差异，1株UC来源的分离株对UC黏蛋白的亲和力显著升高（p [原文内容缺失]）。 研究结论：本初步研究数据表明，阿克曼氏菌与脱硫弧菌属临床分离株的黏蛋白结合能力存在个体差异。本研究证实，黏蛋白微阵列平台可用于研究健康与疾病状态下细菌与结肠黏蛋白的相互作用能力。